Probing the role of copper in the biosynthesis of the molybdenum cofactor in Escherichia coli and Rhodobacter sphaeroides.
Probing the role of copper in the biosynthesis of the molybdenum cofactor in Escherichia coli and Rhodobacter sphaeroides.
复制标题
探讨铜在大肠杆菌和球形红杆菌生物合成钼辅因子中的作用。
DOI：
10.1007/s00775-007-0279-x
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Hegg,EricL
中科院分区：
文献类型：
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作者：
Morrison,MScott;Cobine,PaulA;Hegg,EricL
Cnx 1G（一种参与拟南芥中钼辅因子（Moco）生物合成的酶）的晶体结构揭示了铜离子结合于异蝶呤中间体的二硫烯单元的显著特征（Kuper等，Nature 430：803-806，2004）。为了进一步表征铜在Moco生物合成中的作用，我们研究了两种Moco依赖性酶，二甲基亚砜还原酶（DMSOR）和硝酸还原酶（NR），在各种铜条件下生长的细胞的体内和/或体外活性。我们发现，无论是大肠杆菌还是球形红细菌，当培养基中铜被耗尽时，DMSOR和NR的活性都没有受到影响。这些数据表明，虽然铜可以利用在莫科生物合成时，它是可用的，铜似乎并不严格要求莫科生物合成在这两种生物体。
The crystal structure of Cnx1G, an enzyme involved in the biosynthesis of the molybdenum cofactor (Moco) inArabidopsis thaliana, revealed the remarkable feature of a copper ion bound to the dithiolene unit of a molybdopterin intermediate (Kuper et al.Nature430:803–806, 2004). To characterize further the role of copper in Moco biosynthesis, we examined the in vivo and/or in vitro activity of two Moco-dependent enzymes, dimethyl sulfoxide reductase (DMSOR) and nitrate reductase (NR), from cells grown under a variety of copper conditions. We found the activities of DMSOR and NR were not affected when copper was depleted from the media of eitherEscherichia coliorRhodobacter sphaeroides. These data suggest that while copper may be utilized during Moco biosynthesis when it is available, copper does not appear to be strictly required for Moco biosynthesis in these two organisms.